laconicd-deprecated/ethereum/eip712/preprocess.go
2023-03-13 12:34:10 +05:30

99 lines
3.2 KiB
Go

// Copyright 2021 Evmos Foundation
// This file is part of Evmos' Ethermint library.
//
// The Ethermint library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The Ethermint library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the Ethermint library. If not, see https://github.com/evmos/ethermint/blob/main/LICENSE
package eip712
import (
"fmt"
"github.com/cerc-io/laconicd/types"
"github.com/cosmos/cosmos-sdk/client"
codectypes "github.com/cosmos/cosmos-sdk/codec/types"
cosmoskr "github.com/cosmos/cosmos-sdk/crypto/keyring"
"github.com/cosmos/cosmos-sdk/types/tx/signing"
authtx "github.com/cosmos/cosmos-sdk/x/auth/tx"
)
// PreprocessLedgerTx reformats Ledger-signed Cosmos transactions to match the fork expected by Ethermint
// by including the signature in a Web3Tx extension and sending a blank signature in the body.
func PreprocessLedgerTx(chainID string, keyType cosmoskr.KeyType, txBuilder client.TxBuilder) error {
// Only process Ledger transactions
if keyType != cosmoskr.TypeLedger {
return nil
}
// Init extension builder to set Web3 extension
extensionBuilder, ok := txBuilder.(authtx.ExtensionOptionsTxBuilder)
if !ok {
return fmt.Errorf("cannot cast TxBuilder to ExtensionOptionsTxBuilder")
}
// Get signatures from TxBuilder
sigs, err := txBuilder.GetTx().GetSignaturesV2()
if err != nil {
return fmt.Errorf("could not get signatures: %w", err)
}
// Verify single-signer
if len(sigs) != 1 {
return fmt.Errorf("invalid number of signatures, expected 1 and got %v", len(sigs))
}
signature := sigs[0]
sigData, ok := signature.Data.(*signing.SingleSignatureData)
if !ok {
return fmt.Errorf("unexpected signature type, expected SingleSignatureData")
}
sigBytes := sigData.Signature
// Parse Chain ID as big.Int
chainIDInt, err := types.ParseChainID(chainID)
if err != nil {
return fmt.Errorf("could not parse chain id: %w", err)
}
// Add ExtensionOptionsWeb3Tx extension with signature
var option *codectypes.Any
option, err = codectypes.NewAnyWithValue(&types.ExtensionOptionsWeb3Tx{
FeePayer: txBuilder.GetTx().FeePayer().String(),
TypedDataChainID: chainIDInt.Uint64(),
FeePayerSig: sigBytes,
})
if err != nil {
return fmt.Errorf("could not set extension as any: %w", err)
}
extensionBuilder.SetExtensionOptions(option)
// Set blank signature with Amino Sign Type
// (Regardless of input signMode, Evmos requires Amino signature type for Ledger)
blankSig := signing.SingleSignatureData{
SignMode: signing.SignMode_SIGN_MODE_LEGACY_AMINO_JSON,
Signature: nil,
}
sig := signing.SignatureV2{
PubKey: signature.PubKey,
Data: &blankSig,
Sequence: signature.Sequence,
}
err = txBuilder.SetSignatures(sig)
if err != nil {
return fmt.Errorf("unable to set signatures on payload: %w", err)
}
return nil
}